Ever since I was a young child, I have foiled the plans of predators. In elementary school, I chased after the bullies, yanked out of their hands the toys they took away from various children, and threw myself between them and their intended victims of violence.

In middle school, I threatened the boys who sexually harassed the girls, promising that if they ever even thought about laying a finger on me, I would pummel the crap out of them. I went through three years without one incident.

In high school, a bully at my summer program came after me. In an intuitive Aikido-type move, I flipped him over when he lunged at me — leaving him sprawled on the concrete, swearing. In college, another bully at another summer program (a former military man at that) wouldn’t stop “play hitting” me, so I forcefully slammed him against a wall. He never bothered me again.

Throughout my 20s, I intervened in countless violent situations — a man holding a woman at knife point on a subway platform, a woman violently threatening her child in hospital lobby, a man hitting his son on a tourist promenade.

That decade, I studied and taught full-contact self-defense. I biked in the hills at midnight and wandered the streets at 3:00 a.m. I pushed the envelope of response to street harassment — hitting two soldiers ogling my breasts, a security guard “hey-baby”ing me non-stop, and a subway passenger who felt up my ass.

I seized life. I took risks. I was independent, powerful, defiant, free.

And then I was in pain. And then I had limited mobility. And then I stopped taking physical risks, because I could never be sure if my body would come through for me. And then I stopped taking on predators, because I could never be sure if I’d take them down.

Two weeks ago, I was walking up the street towards my house, when I heard violent yelling. As I neared the source of the clamor, I saw that a man was circling two women, who were yelling at him to get away. Instinctively, my body geared up to run over and stop him. And then I remembered.